What do the letters RQ on hazmat packages mean?
The letters RQ stand for Reportable Quantity; in other words, if an RQ amount, governed by 172.101, appendix A, is released into the environment, EPA wants to know about it. The EPA notification of an RQ release is 15 minutes. Incident and Emergency reporting is governed in 49 CFR 171.15, 16, and 40 CFR 302.